Strap adjustment buckle for helmets



FIG. 1 is a rear perspective view of a strap adjustment buckle for helmets showing my design, the straps being shown in broken lines for illustrative purposes only;

FIG. 2 is a front elevational view thereof;

FIG. 3 is an end elevational view taken from the left side of FIG. 2;

FIG. 4 is a bottom plan view thereof;

FIG. 5 is a top plan view thereof; and, 

The ornamental design for a strap adjustment buckle for helmets, as shown and described. 